Of the many kinds of wisdom a father can pass on to his son, there is one where Rod Stewart is a world-renowned expert. It’s called how to win the hearts of beautiful women.

Rod could easily write a book on the subject. Instead, he has become a kind of Jedi Master in the art of seduction to his eldest son Sean.

“My dad gives me lots of advice in many areas of my life, including getting girls,” says Sean, 34, in his first-ever interview.

“He says to me, ‘You need to make a girl laugh, charm her, make her feel beautiful, make her feel special and be a gentleman... then you’re in.’

Rod Stewart with his son Sean at Glasgow Airport (Image: Daily Mirror)

“I mean... he should know. I’ve most definitely learned from the best. He has given me the secrets of the young Jedi Stewart. He will be really disappointed if I don’t find myself a nice lady now. Although he’s done with getting married... he is definitely done now.”

Rod, now 70, three-times wed and a father of eight, is happily settled with third wife Penny Lancaster. Another pearl of wisdom he may need to pass on in future is his undoubted skill at staying on good terms with the beautiful women he has left behind.

Just to make sure he’s on the right track with his dates, Sean sometimes takes them back to his dad’s Beverly Hills mansion for the “once over”.

“A few of them I do take home for my dad to approve,” says Sean. “They get so excited – he’s the biggest rock star in the world.

“He will give them a little look, and at this point their mums are also excited because they grew up with him.”

So far, so glamorous. But life hasn’t always been so settled and happy for Sean Stewart. His 20s were a troubled time living in a world of what he now calls simply “pain”.

Kimberly Stewart and brother Sean Stewart (Image: Getty)

That came from years of torment at his Los Angeles private school, where “the kids were mean”.

With so much bottled-up pain inside, Sean developed a reckless approach to life that led him into constant trouble. There were numerous arrests, most notably in 2001 when he was charged with assault after defending himself in a bar fight in Malibu. Many wrote him off as just another bratty son of a rock star.

Speaking for the first time about his torment, Sean looks back now and says: “I was lost. Everybody has hurt and pain inside them, but some people take it out on hurting themselves. I dealt with it by drinking and doing other things. My pain started when I was bullied in high school. I was a skinny little kid, I was scrawny, I was picked on, beat up, made fun of. I was dyslexic and I have OCD. They nicknamed me ‘Stupid Stewart’ at school.

Sean says it was Rod’s love that proved vital in helping him leave the past behind.

“I don’t think I had a drug addiction and it wasn’t hard at all to stop drinking,” he says, “When I got to 30 I realised that I wanted to turn my life around, I wanted to find my way and stop hurting myself.

(Image: Instagram/therealseanstewart)

“I decided to take my problems and turn them into success stories, and shove those success stories down the throats of anyone who had ever doubted me.

“My occupation back then was that I was lost. I played soccer to a high standard, but then I got lost. The bullying really affected my self-esteem. I got a lot of love and support from my father, my mother and sister Kim. It was especially my dad, he was always sympathetic to what I went through.

“I’m past that alcohol and drug thing now since I was 30. It’s been over three years.”

Sean had just finished a SoulCycle class when we met for breakfast at the Beverly Hills Hotel. He is bursting with energy and excited to talk about his new clothing range Dirty Weekend, which shares its name with a track from his dad’s hit 1978 album Blondes Have More Fun.

It’s affordable. Not high end, not flash... just like Sean really.

Most important to him, he has his beloved father’s support. Clearly, he idolises Rod and they are very close. They shop together, lunch together, play football together, talk about cars together and most importantly, make each other laugh.

Sean, who has more than a little of the young Rod the Mod about his looks, says: “We are the same person. We have the same humour – the same little-boy charm that he had when he was 30.”

As a child, Sean often went on Rod’s tours and he had an early introduction to the over-the-top antics of a rock star.

“Girls would take off their tops and throw their bras on the stage,” he recalls. “It was f****** awesome, I was like, ‘My dad is the coolest guy in the world’.

“Then he would come offstage and pick me up and afterwards he would teach me how to destroy hotel rooms. We would get the key to the band’s room and play pranks on them – mess up their beds, put chickens in their rooms. It was the best. He was a proper rock star.

“He has chilled out now but he’s still loves a good prank. And he won’t give up singing for another 20 years. No way – he’s still a lot of fun.”

Fun is a high priority for all the Stewarts, says Sean, whose own high jinks landed him in a cell only last month.

On his way to do volunteer work to help earthquake victims in Haiti with his sisters Kimberly, 35, and Ruby, 27, he decided to jump on to the luggage conveyor belt for a laugh.

“I went all of the way around and there was security – it was pretty scary,” he says. “I won’t do that again, but it was annoying because we were going to Haiti to help people.”

He and his sisters have almost finished filming a reality show for the E! Channel. Sean says their dad may feature, as will his mother Alana (Rod’s first wife) and her previous husband, actor George Hamilton. It’s like a real-life Modern Family, Sean explains.

He is close to all of his brothers and sisters, including Renee, 22, and Liam, 20, from his father’s marriage to Aussie model Rachel Hunter, 45, and the two youngest – Alastair, nine, and Aiden, four, whose mum is Penny Lancaster.

Rachel, who divorced Rod in 2006, is still “very much part of his life” says Sean. “I’m close to all of my siblings,” he adds. “The youngest two are great kids. I play soccer with Alastair and he’s a great swimmer.

“There are lots of celebrity families but there aren’t many that are as interesting as us. We are fun – we have fun, when we all come together you should see what happens. It’s a big party when we all get together. We’re like the Brady Bunch on acid.”

Sean smiles the widest when I ask about his niece Delilah, Kimberley’s daughter, who turned three in September. Her dad is Hollywood actor Benicio Del Toro but he and Kim are not together.

“Being an uncle is the most amazing thing in the world,” he says. “I adore Delilah. She loves me and I love her. I see her all the time and her dad sees her all the time too. He and Kim are doing a great job of co-parenting. He is always at the house and takes her for weekends.

“My dad is a really great grandfather. He spends a lot of time with Delilah too. It’s great to see.”

Rod, worth around £200million, may have splashed out on his mansion in Beverly Hills and another one in Essex but Sean says he donates “millions each year” to charity without any fanfare and encourages his children to point their lives in a similar direction.

“I’ve always done charity work,” says Sean. “I ran a soccer camp for three years in Downtown LA, then Kim, Ruby and I went to Haiti to visit the orphanages.”

He adds: “My dad taught us how to give back. He donates anonymously – he doesn’t do it to look good. But he spends millions. And we were brought up to appreciate money. I’ve learned to work hard for it.”

Determined to be a success in business Sean is to add a bar and restaurant called Hot Legs – after Rod’s hit song – to his portfolio. There’s a special tequila cocktail too.

“Some of the most successful men in the world were bullied and have dyslexia,” he points out.

But ask him for his ultimate ambition and without any hesitation, he tells me: “I want to get married and have kids now. The most successful thing in the world would be to be the best father– and I learned that from my dad.”

To find out more about Sean's Dirty Weekend clothing line go towww.dirtyweekend.la or @dirtyweekendapparel on Instagram